diff --git a/package.json b/package.json
index 3909fcf04..ba02559b8 100644
--- a/package.json
+++ b/package.json
@@ -61,6 +61,7 @@
     "@web/test-runner-browserstack": "^0.5.0",
     "@web/test-runner-commands": "^0.6.1",
     "@web/test-runner-playwright": "^0.8.8",
+    "@yarnpkg/lockfile": "^1.1.0",
     "babel-polyfill": "^6.26.0",
     "bundlesize": "^1.0.0-beta.2",
     "chai": "^4.2.0",
diff --git a/yarn.lock b/yarn.lock
index 11a8e126e..63baba223 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -3008,6 +3008,11 @@
   resolved "https://registry.yarnpkg.com/@webcomponents/webcomponentsjs/-/webcomponentsjs-2.5.0.tgz#61b27785a6ad5bfd68fa018201fe418b118cb38d"
   integrity sha512-C0l51MWQZ9kLzcxOZtniOMohpIFdCLZum7/TEHv3XWFc1Fvt5HCpbSX84x8ltka/JuNKcuiDnxXFkiB2gaePcg==
 
+"@yarnpkg/lockfile@^1.1.0":
+  version "1.1.0"
+  resolved "https://registry.yarnpkg.com/@yarnpkg/lockfile/-/lockfile-1.1.0.tgz#e77a97fbd345b76d83245edcd17d393b1b41fb31"
+  integrity sha512-GpSwvyXOcOOlV70vbnzjj4fW5xW/FdUF6nQEt1ENy7m4ZCczi1+/buVUPAqmGfqznsORNFzUMjctTIp8a9tuCQ==
+
 a-sync-waterfall@^1.0.0:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/a-sync-waterfall/-/a-sync-waterfall-1.0.1.tgz#75b6b6aa72598b497a125e7a2770f14f4c8a1fa7"